The provincial jail in Windsor, Ont., is still locked down three days after police had a tip there was contraband on the premises.
"Over the weekend, institution officials received some information that they deemed to be credible that there was contraband in the institution. So on Sunday afternoon they locked down the institution and began the search which, as I say, still continues," said Stuart McGetrick, a spokesman for the Correctional Services ministry.
The jail's 130 inmates will be kept in their cells until the search has been completed.
Inmates who have scheduled court appearances will be allowed out of their cells to attend their hearings.
McGetrick said the lockdown is not related to a fight on Saturday that left a prisoner severely injured in hospital.
Jesse Brode, 19, is reported to be paralyzed from the waist down after he was beaten by several other prisoners.
Police are investigating, but have released no other information about the fight.